Coexisting myasthenia gravis, myositis, and polyneuropathy induced by ipilimumab and nivolumab in a patient with non-small-cell lung cancer

Abstract

Rationale:Immune checkpoint inhibitors have led to the development of new approaches for cancer treatment with positive outcomes. However, checkpoint blockade is associated with a unique spectrum of immune-related adverse events (irAEs), which may cause irreversible neurological deficits and even death.Patient concerns:We presented a case of a 57-year-old man with non-small-cell lung cancer.who developed ptosis, dyspnea, and muscle weakness as initial symptoms with progression after the treatment with ipilimumab and nivolumab.Diagnoses:Myasthenia gravis was confirmed by serum acetylcholine receptor antibody and single fiber electromyography. Myositis was identified by high level of serum creatine phosphokinase and electromyography. Polyneuropathy was identified by nerve conduction study.Interventions:The patient underwent treatment with steroid and pyridostigmine. Respiratory rehabilitation was also performed.Outcomes:Dyspnea and muscle weakness improved gradually. Ipilimumab and nivolumab were permanently discontinued.Lessons:This case has increased the clinical awareness by indicating that the checkpoint inhibitors-related neurological irAEs could be complicated and simultaneously involve multiple neurological systems. Early recognition and complete evaluation are critical in clinical practice.

Immune checkpoint inhibitors‐induced neuromuscular toxicity: From pathogenesis to treatment

“…Impairment of neuromuscular transmission on electrodiagnostic tests is not often reported. Noteworthy, abnormalities usually found in MG, including CMAP decrement to low‐frequency repetitive nerve stimulation at 3 Hz and increased jitter on single fiber ENMG, were identified only in half of the patients tested, revealing that the positive prediction rate of electrodiagnosis is relatively low . The reason for this observation has been attributed to the presence of concurrent myositis contributing to clinical findings …”

“…Decrement on low‐frequency repetitive nerve stimulation at a frequency of 3 Hz and increased jitter on single fiber EMG 50%…”

Myasthenia gravis and myopathy after nivolumab treatment for non‐small cell lung carcinoma: A case report

“…In this case report, acute myopathy and myasthenia gravis was noted. The combination of these two conditions suggests very rare dysimmune toxicity, and several cases of myasthenia gravis with hyperCKemia have been reported worldwide . It is postulated that the simultaneous formation of AChR antibody and anti‐striational antibodies is required to develop myasthenia gravis with myositis.…”

“…They rarely cause fatal side effects, but recently, specific immune‐related adverse events (irAEs) involving neuromuscular systems have been reported . Several cases of myasthenia gravis with myopathy have already been published, but the exact mechanisms of these conditions are still unclear . Here, we report a case of myasthenia gravis and acute myopathy in a patient treated with nivolumab.…”

Trouble at the junction: When myopathy and myasthenia overlap

“…Since the introduction of immune checkpoint inhibitors (ICI) in cancer immunotherapy, several cases of myasthenia gravis and immune‐mediated myopathies in ICI‐treated patients have been reported . ICI‐induced neuromuscular complications have emerged as rare but serious adverse effects of these medications and generally develop within 3 months of initiating therapy . Only a minority of patients have pre‐existing myasthenia gravis or myositis .…”